Not sure. Doubt they would harm you if eaten but if they are actually able to be eaten is another matter. I would assume they are very woody and strong flavored. Only one way to find out.

Rodney

I think also they would be woody, You can remove the woody part , get to the core. It will be similar to cabbage core. You can cook it, make pickle with it, I imaging it should have a mustardy taste when raw.